KANDAHAR, Afghanistan - Heads have rolled within Afghanistan's security apparatus with the police chief in Kandahar province and two other senior officials dismissed in the wake of a devastating prison break.

Police chief Syed Aqa Saqib and the other two have not only been fired but are also being investigated for their possible role in the deadly attack on Sarposa prison.

The dismissals and police investigation were announced Thursday, the same day that Canada said it would spend $4 million to help refurbish Kandahar's largest prison.

"All three of them will be under investigation,'' Ahmed Wali Karzai, head of the provincial council and brother of President Hamid Karzai, told The Canadian Press.

Unlike the increasingly competent Afghan army, the national police force is so ridden with corruption and inefficiency that NATO soldiers are wary of revealing basic information in front of uniformed officers.

Just a few weeks ago, Saqib told The Canadian Press that men wearing his force's uniform had kidnapped people, robbed from locals and stolen cars.

He warned that men in police uniforms could be a threat to Canadian and other foreign troops. But he said these acts were committed by people wearing fake uniforms counterfeited abroad, in a number of unspecified countries.

Ahmed Wali Karzai said his brother had been briefed by a group of investigators who returned to the capital after a fact-finding mission in Kandahar.

Officials from the Interior Ministry and Justice Department led the delegation that probed the incident, in which a suicide truck-bombing and a rocket assault helped hundreds of suspected insurgents escape.

Karzai said he did not know whether any of the information they uncovered led to the firing of Saqib and the province's chief of security. But he said the poor police performance in the fiasco was enough to cause the dismissal.

"There was a lack of organization among the security forces,'' Karzai said.

"The police did not respond well.''

Meanwhile, the Canadian government announced it would spend $4 million to rebuild and renovate Sarposa.

Signs of carnage still lingered at the prison site Thursday, almost two weeks after the explosive assault.

Piles of rubble, bits of barbed wire, charred and twisted police vehicles, and empty boots and sandals lay strewn in the debris.

Up to $2 million of the Canadian money will go to urgent repairs as a result of the attack, while the rest is being spent on more routine things such as renovations, rewiring and human-rights training for officials.

The Canadian government has paid $17,000 for a local contractor to install a temporary metal wall outside the jail, which is already in place.

The blue metal barrier was installed over four days within the last week. A more permanent structure will be erected over the coming months.

A Canadian military engineer overseeing the project said he was thrilled with the speed and efficiency of the local Afghan contractor who put up the temporary barrier.

"Excellent,'' said warrant officer Mike Budden of Moncton, N.B., as he toured the prison.

"The guy's really on the go ... Progress was really fast. We're quite pleased.''

The Afghan interior ministry said in a statement that Col. Maitullah Khan had been appointed to replace Saqib.

"The investigation shows some officials neglected their duties,'' said the statement.

"Therefore the government of Afghanistan has decided to sack General Sayed Aqa Saqib, the provincial police chief of Kandahar.''

The statement said that the local head of the intelligence agency and the head of police criminal investigations were also dismissed.

The government also announced that the cases have been forwarded to the attorney general's office for further investigation.